Anura3D Free Software Community

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There is increasing interest in the MPM (and its variants, such as GIMP, CPDI1, CPDI2, etc.) as a means of modelling problems in which very large deformations occur, e.g. in the study of landslides. The purpose of this mini-symposium is to provide a forum for presenting advances in the method, e.g. improving the accuracy (including convergence and benchmark problems), dealing with numerical issues, modelling of coupled problems, computational efficiency and applications to real world problems. Abstracts will be accepted until at least the end of November (https://sites.durham.ac.uk/emi2020-ic/abstracts-submission/).

The next workshop and training course will be held at Virginia Tech in partnership with the American MPM community from Monday 9th to Thursday 11th September.
More information at http://www.mpmworkshop.com/.

A special session on the material point method in computational geomechanics will be held at the 16th IACMAG and is orrganised by Dr. Francesca Ceccato and Prof. Paolo Simonini (University of Padova).
The 16th International Conference of the International Association for Computer Methods and Advances in Geomechanics will be held in Turin, Italy, 1 July - 4 July 2020.
More information is available at the following link:http://www.symposium.it/en/events/2020/16th-international-conference-of-...

08-10 January 2019
Churchill College, Cambridge, United Kingdom

We are delighted to invite you to join us at the Second International Conference on the Material Point Method for “Modelling Large Deformation and Soil–Water–Structure Interaction” organised by the Anura3D MPM Research Community in January 2019 in Cambridge. This is the second conference following the successfull first event in Delft (2017).

The aim is to provide an international forum for presenting and discussing the latest developments in both the fundamental basis and the applicability of state-of-the-art computational methods that can be effectively used for solving a variety of large deformation problems in geotechnical and hydraulic engineering. Special focus is on the numerical modelling of interaction between soils, water and structures where the interface and transition between solid and fluid behaviour plays an essential role.

For more information and the latest news regarding the conference programme and registration, please visit our website at mpm2019.eu.

We are looking forward to welcoming you in Cambridge in January 2019!The MPM 2019 Organising Committee

Modelling large deformation and soil–water–structure interaction using the material point method

Large deformation and soil–water–structure interaction problems exist in many environmental and civil engineering problems, such as landslides and slope instabilities, installation of piles in saturated soils, settlement due to consolidation processes, fluidisation and sedimentation processes in submerged slopes, internal erosion in dykes, and scouring around offshore structures.

The material point method (MPM) is a numerical approach capable of modelling large deformations and, within the framework of the Anura3D MPM Research Community, it has been further developed to cope with soil–water–structure interaction.

The Anura3D v2017.2 MPM software uses a dynamic explicit MPM formulation. It is capable of simulating 1- and 2-phase materials and free surface water. A fully coupled hydro-mechanical approach is implemented to model the interaction between soil and water phases in saturated porous media. Contact problems can be solved using a contact algorithm. A library of constitutive laws is included as well as an interface for external user defined soil models.

Tutorials
Course participants will gain experience as users of the Anura3D v2017.2 MPM software. During training lectures, the attendees will learn first-hand capabilities of MPM by means of a set of practical exercises that will be undertaken following a tutorial specially designed for the course. The tutorial will include the following exercises:

The Anura3D MPM Research Community is pleased to announce its first US workshop and training course on the material point method (MPM). The events will take place at the University of California, Berkeley.

WORKSHOP - Tuesday May 8th, 2018

The workshop is an opportunity for the MPM community to present their work, exchange ideas and expand their knowledge. It is open to both academics and practitioners who would like to share their or who would like learn more about MPM.

People who would like to give a presentation should contact Dr. James Fern.

Date: Tuesday May 8th, 2018

Hospitality fee: USD 60 (Anura3D members should request an invitation)

Large deformation and soil–water–structure interaction exists in many environmental and civil engineering problems, such as landslides and slope instabilities, installation of piles in saturated soils, settlement due to consolidation processes, fluidisation and sedimentation processes in sub-merged slopes, internal erosion in dykes, and scouring around offshore structures. Modelling these processes is challenging due to hydro-mechanical coupling, large deformation, and contact problems.

Modelling large deformation and soil–water–structure interaction using the material point method

Friday, 29 September 2017
Hamburg University of Technology (TUHH), Germany

Large deformation and soil–water–structure interaction exists in many environmental and civil engineering problems, such as landslides and slope instabilities, installation of piles in saturated soils, settlement due to consolidation processes, fluidisation and sedimentation processes in sub-merged slopes, internal erosion in dykes, and scouring around offshore structures. Modelling these processes is challenging due to hydro-mechanical coupling, large deformation, and contact problems.

The material point method (MPM) is a numerical approach capable of modelling large deformations and recently, within the framework of the MPM Research Community, it has been extended to cope with soil–water–structure interaction.

The Anura3D v2017.1 software uses a dynamic explicit MPM formulation based on a single set of material points. This is capable of simulating 1- and 2-phase materials and free surface water. A fully coupled hydro-mechanical approach is implemented to model the interaction between soil and water phases in saturated porous media, which is understood as a continuum mixture of solid skeleton and pore fluid. Additionally, contact problems can also be solved since a contact algorithm is available. Finally, a library of material constitutive laws is included as well as a umat style interface for external user defined soil models subroutines.

Modelling large deformation and soil–water–structure interaction using the material point method

12–13 January 2017
Deltares, Delft, The Netherlands

Large deformation and soil–water–structure interaction exists in many environmental and civil engineering problems, such as landslides and slope instabilities, installation of piles in saturated soils, settlement due to consolidation processes, fluidisation and sedimentation processes in submerged slopes, internal erosion in dykes, and scouring around offshore structures. Modelling these processes is challenging due to hydro-mechanical coupling, large deformation, and contact problems.
The material point method (MPM) is a point-based numerical approach capable of modelling large deformations and recently, within the framework of the MPM Research Community, it has been extended to cope with complicated soil–water–structure interactions.

10–13 January 2017
Deltares Delft, The Netherlands

We are delighted to invite you to join us at the First International Conference on the Material Point Method for “Modelling Large Deformation and Soil–Water–Structure Interaction” organised by the Anura3D MPM Research Community in January 2017 in Delft. This is the first conference following a series of international workshops and symposia previously held in Padova (2016), Barcelona (2015), Cambridge (2014) and Delft (2013).

The aim of the conference is to provide an international forum for presenting and discussing the latest developments in both the fundamental basis and the applicability of state-of-the-art computational methods that can be effectively used for solving a variety of large deformation problems in geotechnical and hydraulic engineering. Special focus is on the numerical modelling of interaction between soils, water and structures where the interface and transition between solid and fluid behaviour plays an essential role.

For more information and the latest news regarding the conference programme and registration, please regularly visit our website at www.mpm2017.eu.

We are looking forward to welcoming you in Delft in January 2017!The MPM 2017 Organising Committee

High-order material point method

Abstract
The material point method (MPM) is a meshfree mixed Lagrangian-Eulerian method which utilizes moving Lagrangian material points that store physical properties of a deforming continuum and a fixed Eulerian finite element mesh to solve the equations of motion for individual time steps. MPM proved to be successful in simulating mechanical problems which involve large deformations of history-dependent materials. The solution on the background grid is found in MPM by a variational formulation. The integrals resulting from this formulation are numerically approximated by using the material points as integration points. However, the quality of this numerical quadrature rule decreases when the material points become unevenly distributed inside the mesh.

It is common practice in MPM to adopt piecewise linear basis functions for approximating the solution of the variational form. A problem arises from the discontinuity of the gradients of these basis functions at element boundaries leading to unphysical oscillations of computed stresses when material points cross element boundaries. Such grid crossing errors significantly affect the quality of the numerical solution and may lead to a lack of spatial convergence.

First International Conference on the Material Point Method for
Modelling Large Deformation and Soil–Water–Structure Interaction

10–13 January 2017, Delft, The Netherlands

We are delighted to invite you to join us at the First International Conference on the Material Point Method for “Modelling Large Deformation and Soil–Water–Structure Interaction” organised by the MPM Research Community in January 2017 in Delft. This is the first conference following a series of international workshops and symposia previously held in Barcelona (2015), Cambridge (2014) and Delft (2013) in the context of the FP7 Marie-Curie project MPM-DREDGE.

The aim of the conference is to provide an international forum for presenting and discussing the latest developments in both the fundamental basis and the applicability of state-of-the-art computational methods that can be effectively used for solving a variety of large deformation problems in geotechnical and hydraulic engineering. Special focus is on the numerical modelling of interaction between soils, water and structures where the interface and transition between solid and fluid behaviour plays an essential role.

Papers on any aspect of these subjects are most welcome. Active discussion on key topics will be facilitated through invited keynote lectures. In addition, the partners of the MPM-DREDGE project will present the highlights of their research programme, achieved through intense collaboration between industry and academia. The results include validated computational tools based on the material point method to improve the understanding of installation of geocontainers, liquefaction of submarine slopes, landslides and erosion around offshore and near-shore structures.

Abstract
Approximately 400 kilometres of Dutch sea dikes are protected by bituminous concrete revetments to prevent damage from erosion and repeated wave attacks during storms. The numerical analysis of sea dikes subjected to cyclic wave loading needs to consider the behaviour of the bituminous concrete revetment, and the behaviour of the subsoil including the generation and dissipation of the excess pore pressures, as well as the interaction between the revetment and subsoil. This thesis develops and evaluates numerical methods for investigating this problem, using the dynamic Finite Element Method with the coupling of plate and volume elements.

In dynamic finite element analysis, the arbitrary selected boundary generates wave reflections which normally causes oscillation problems. Absorbing boundary conditions are therefore adopted to minimise the wave reflection at the artificial boundaries. The effects of the absorbing boundary conditions are investigated in detail for both solid and water phases, and appropriate sets of parameters are recommended.

Soil–water interaction

Soil–water interaction exists in many environmental and civil engineering problems, such as landslides induced by rainfall, fluidisation and sedimentation processes in submerged slopes, internal erosion in dykes, scouring around offshore structures, settlement due to consolidation processes and installation of piles in saturated soils. Modelling these processes is challenging due to soil–water coupling and large deformation.
MPM is a point-based numerical method capable of modelling large deformations and recently, within the framework of the MPM Research Community, it has been extended to cope with complicated soil-fluid interactions.
This training course focuses on presenting those MPM formulations cable of simulating the interaction between soil and water phases. Two different approaches will be addressed. In the first one, a single set of material points describes the behaviour of saturated porous media understood as a mixture of solid skeleton and pore fluid. The second approach describes the movement of each constituent (i.e. solid and fluid) individually by means of two sets of material points, thereby enabling the simulation of free water and the in and outflow, as well as fluidisation and sedimentation processes.

A hybrid particle-mesh method for simulating free surface flows

Abstract
Hybrid particle-mesh methods attempt to combine the advantages of Eulerian and Lagrangian methods: Lagrangian particles are used for the advection, whereas a Eulerian background grid is used for computing the particle interactions. Such a hybrid approach is expected to have several benefits when simulating flows involving free surfaces or material interfaces: the particles can be efficiently used to track the free surface, while the background grid can be used to solve the governing Navier-Stokes equations and impose the incompressibility constraint in a convenient manner. The prospects of these hybrid particle-mesh methods for simulating incompressible fluid flows involving a free surface are assessed in this thesis. More specifically, the feasibility of setting-up a numerical wave flume using hybrid particle-mesh methods is investigated.

First International Conference on the Material Point Method for
Modelling Large Deformation and Soil–Water–Structure Interaction

10–13 January 2017, Delft, The Netherlands

We are delighted to invite you to join us at the First International Conference on the Material Point Method for “Modelling Large Deformation and Soil–Water–Structure Interaction” organised by the MPM Research Community in January 2017 in Delft. This is the first conference following a series of international workshops and symposia previously held in Barcelona (2015), Cambridge (2014) and Delft (2013) in the context of the FP7 Marie-Curie project MPM-DREDGE.

The aim of the conference is to provide an international forum for presenting and discussing the latest developments in both the fundamental basis and the applicability of state-of-the-art computational methods that can be effectively used for solving a variety of large deformation problems in geotechnical and hydraulic engineering. Special focus is on the numerical modelling of interaction between soils, water and structures where the interface and transition between solid and fluid behaviour plays an essential role.

Papers on any aspect of these subjects are most welcome. Active discussion on key topics will be facilitated through invited keynote lectures. In addition, the partners of the MPM-DREDGE project will present the highlights of their research programme, achieved through intense collaboration between industry and academia. The results include validated computational tools based on the material point method to improve the understanding of installation of geocontainers, liquefaction of submarine slopes, landslides and erosion around offshore and near-shore structures.

Abstract
The paper describes a three-phase single-point material point method formulation of coupled flow (water and air) for hydro-mechanical analysis of geotechnical problems involving unsaturated soils. The governing balance and dynamic momentum equations are discretised and adapted to material point method characteristics: an Eulerian computational mesh and a Lagrangian analysis of material points. General mathematical expressions for the terms of the set of governing equations are given. A suction-dependent elastoplastic Mohr–Coulomb model, expressed in terms of net stress and suction variables is implemented. The instability of a slope subjected to rain infiltration, inspired from a real case, is solved and discussed. The model shows the development of the initial failure surface in a region of deviatoric strain localisation, the evolution of stress and suction states in some characteristic locations, the progressive large strain deformation of the slope and the dynamics of the motion characterised by the history of displacement, velocity and acceleration of the unstable mass.

Abstract
This paper presents the formulation and implementation of a numerical procedure based on material point method (MPM) to solve fully coupled dynamic problems that undergo large deformations in saturated soils. The key aspect of this formulation is that it considers two sets of Lagrangian material points to represent soil skeleton and pore water layers. The accuracy of the method is tested by comparing the results to some analytical solutions of consolidation theory. The developed method has been applied to model progressive failure of river levees to illustrate the practical applications. The numerical results show the robustness of the proposed method with regard to large deformations that undergo rapid failure mechanisms.

Deltares started a collaboration with the universities of Cambridge, Barcelona and Hamburg to establish a research community for the numerical modelling of soil interacting with water. The aim is to further develop a dynamic calculation method, the Material Point Method (MPM), making it suitable to apply for contractors, designers and engineering companies. MPM is used to analyse large deformations and large movements of soil and water, for example to simulate the installation of a piled foundation, the failure of a dike or the sliding of an underwater slope. Further development of MPM will enable us to improve our understanding of the consequences of large soil deformations. The software will be validated using laboratory and field experiments.